Would you like CAS on our forums?

Well, on my forum, you must post 6 posts to be able to visit the rest of the forum. But I want to alter it a bit, I would like to make so if you read through topics you can find a code. Using that code, you must enter it in to a Code Authorization System (or CAS). So to put it simply, I'm saying...

1. User finds code and goes on a CAS page.2. They enter the code and the whole forum becomes visible to them.

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